<template>
  <div>
    <!--面包屑导航区-->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>分类参数</el-breadcrumb-item>
    </el-breadcrumb>
    <!--卡片试图区-->
    <el-card>
      <!--头部警告区域-->
      <el-alert
        title="注意：只允许为第三级分类设置相关参数！"
        type="warning"
        :closable="false"
        show-icon>
      </el-alert>
      <!--选择商品分类区-->
      <el-row class="cat-opt">
        <el-col>
          <span>选择商品分类：</span>
          <!--选择商品的级联选择框-->
          <el-cascader
            expand-trigger="hover"
            :options="cateList"
            :props="cateProps"
            v-model="selectedKeys"
            @change="handleChanged"
            clearable
            popper-class="my-cascader-dropdown">
          </el-cascader>
        </el-col>
      </el-row>
      <!--tag页签区域-->
      <el-tabs v-model="activeName" @tab-click="handleTagClick">
        <!--添加动态参数的面板-->
        <el-tab-pane label="动态参数" name="many">
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加参数</el-button>
          <!--动态参数表格-->
          <el-table :data="manyTableData" border stripe>
            <el-table-column type="expand">
              <!--循环渲染tag标签-->
              <template #default="scope">
                <el-tag v-for="(item, i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i, scope.row)">{{item}}</el-tag>
                <!--输入文本框-->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!--添加的按钮-->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <el-table-column type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作" #default="scope">
              <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
              <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeParam(scope.row.attr_id)">删除</el-button>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!--添加静态属性的面板-->
        <el-tab-pane label="静态属性" name="only">
          <el-button type="primary" size="mini" :disabled="isBtnDisabled" @click="addDialogVisible = true">添加属性</el-button>
          <!--静态属性表格-->
          <el-table :data="onlyTableData" border stripe>
            <el-table-column type="index"></el-table-column>
            <el-table-column type="expand">
              <!--循环渲染tag标签-->
              <template #default="scope">
                <el-tag v-for="(item, i) in scope.row.attr_vals" :key="i" closable @close="handleClose(i, scope.row)">{{item}}</el-tag>
                <!--输入文本框-->
                <el-input
                  class="input-new-tag"
                  v-if="scope.row.inputVisible"
                  v-model="scope.row.inputValue"
                  ref="saveTagInput"
                  size="small"
                  @keyup.enter.native="handleInputConfirm(scope.row)"
                  @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!--添加的按钮-->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作" #default="scope">
              <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
              <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeParam(scope.row.attr_id)">删除</el-button>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>
    <el-dialog :title="'添加' + titleText" :visible.sync="addDialogVisible" width="50%" @close="addDialogClosed">
      <el-form :model="addForm" :rules="addFormRules" ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <div slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </div>
    </el-dialog>
    <!--修改参数的对话框-->
    <el-dialog :title="'修改' + titleText" :visible.sync="editDialogVisible" width="50%" @close="editDialogClosed">
      <el-form :model="editForm" :rules="editFormRules" ref="editFormRef"  label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <div slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </div>
    </el-dialog>
  </div>
</template>

<script>
export default {
  data () {
    return {
      // 商品分类列表
      cateList: [],
      // 级联选择框的配置对象
      cateProps: {
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },
      // 级联选择框双向绑定到的数组
      selectedKeys: [],
      // 被激活的页签的名称，默认第一个
      activeName: 'many',
      // 动态参数的数据
      manyTableData: [],
      // 静态属性的数据
      onlyTableData: [],
      // 控制添加对话框的显示与隐藏
      addDialogVisible: false,
      // 添加参数的表单数据
      addForm: {},
      // 添加参数的验证规则
      addFormRules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      },
      // 修改对话框表单数据对象
      editForm: {},
      // 控制编辑对话框的显示与隐藏
      editDialogVisible: false,
      // 编辑对话框验证规则
      editFormRules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      }
    }
  },
  created () {
    this.getCateList()
  },
  methods: {
    // 获取所有的商品分类列表
    async getCateList () {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status !== 200) return this.$message('获取商品分类失败')
      this.cateList = res.data
    },
    // 级联选择框选中想变化时触发这个函数
    handleChanged () { // 控制级联选择器选中的范围
      if (this.selectedKeys.length !== 3) {
        this.selectedKeys = []
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      this.getParamsData()
    },
    // Tag页签点击事件的处理函数
    handleTagClick () {
      this.getParamsData()
    },
    // 获取参数的列表数据
    async getParamsData () {
      // 证明选中的不是三级分类
      if (this.selectedKeys.length !== 3) {
        this.selectedKeys = []
      }
      // 证明选中该的是三级分类
      // 根据所选分类的Id，和当前所处的面板，获取对应的参数
      const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes`, { params: { sel: this.activeName } })
      if (res.meta.status !== 200) return this.$message.error('获取参数列表失败！')
      // 将对象数组每一项的attr_vals都转成数组
      res.data.forEach(item => {
        // 判断attr_vals字符串是否为空
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        // 控制文本框的显示与隐藏
        item.inputVisible = false
        // 文本框的输入的值
        item.inputValue = ''
      })
      if (this.activeName === 'many') {
        this.manyTableData = res.data
      } else {
        this.onlyTableData = res.data
      }
    },
    addDialogClosed () {
      // 监听添加对话框的关闭事件
      this.$refs.addFormRef.resetFields()
    },
    // 点击确定按钮添加参数
    addParams () {
      this.$refs.addFormRef.validate(async valid => {
        // 验证失败
        if (!valid) return
        // 验证成功
        const { data: res } = await this.$http.post(`categories/${this.cateId}/attributes`, {
          attr_name: this.addForm.attr_name,
          attr_sel: this.activeName
        })
        if (res.meta.status !== 201) return this.$message.error('添加参数失败')
        this.$message.success('添加参数成功')
        this.addDialogVisible = false
        await this.getParamsData()
      })
    },
    // 点击按钮，展示修改的对话框
    async showEditDialog (attrId) {
      // 查询当前参数的信息
      const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes/${attrId}`, {
        params: { attr_sel: this.activeName }
      })
      if (res.meta.status !== 200) return this.$message.error('获取参数失败')
      this.editForm = res.data
      this.editDialogVisible = true
    },
    // 编辑对话框关闭时的处理函数
    editDialogClosed () {
      this.$refs.editFormRef.resetFields()
    },
    // 点击按钮，修改参数信息
    editParams () {
      this.$refs.editFormRef.validate(async valid => {
        if (!valid) return
        const { data: res } = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`, {
          attr_name: this.editForm.attr_name,
          attr_sel: this.activeName
        })
        if (res.meta.status !== 200) return this.$message.error('修改参数失败')
        this.$message.success('修改参数成功')
        await this.getParamsData()
        this.editDialogVisible = false
      })
    },
    // 删除参数
    removeParam (attrId) {
      this.$confirm('此操作将永久删除，是否继续？', '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
      }).then(async () => {
        const { data: res } = await this.$http.delete(`categories/${this.cateId}/attributes/${attrId}`)
        if (res.meta.status !== 200) return this.$message.error('删除失败')
        await this.getParamsData()
        return this.$message.success('删除成功')
      }).catch(() => {
        this.$message.info('已取消删除')
      })
    },
    // 文本框失去焦点，或者摁下Enter都会触发
    handleInputConfirm (row) {
      this.saveAttrVals(row, false)
    },
    // 点击按钮显示文本输入框
    showInput (row) {
      row.inputVisible = true
      // $nextTick方法的作用：当前页面上元素被重新渲染之后，才会执行回调函数中的代码，不然哪个元素没被渲染出来就获取焦点就会失败
      this.$nextTick(_ => {
        // 让文本框自动获得焦点
        this.$refs.saveTagInput.$refs.input.focus()
      })
    },
    // 删除对应的参数和选项
    handleClose (i, row) {
      row.attr_vals.splice(i, 1)
      this.saveAttrVals(row, true)
    },
    // 将对attr_vals的操作保存到数据库
    async saveAttrVals (row, isDelete) {
      // 如果输入的为空或者很多空格
      if (row.inputValue.trim().length === 0 && isDelete === false) {
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      // 如果没有return 则需要做后续处理
      if (!isDelete) {
        row.attr_vals.push(row.inputValue.trim())
      }
      row.inputValue = ''
      row.inputVisible = false
      // 需要发起请求，保存这次操作
      const { data: res } = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`, {
        attr_name: row.attr_name,
        attr_sel: row.attr_sel,
        // 将数组拼接起来，中间以空格分隔
        attr_vals: row.attr_vals.join(' ')
      })
      if (res.meta.status !== 200) return this.$message.error('操作失败')
      return this.$message.success('操作成功')
    }
  },
  computed: {
    // 如果按钮需要被禁用，则返回true，否则返回false
    isBtnDisabled () {
      if (this.selectedKeys.length !== 3) {
        return true
      }
      return false
    },
    // 当前选中的三级分类的id
    cateId () {
      if (this.selectedKeys.length === 3) {
        return this.selectedKeys[2]
      }
      return null
    },
    // 动态计算对话框的标题
    titleText () {
      if (this.activeName === 'many') {
        return '动态参数'
      }
      return '静态属性'
    }
  }
}
</script>

<style scoped lang="less">
.cat-opt {
  margin: 15px 0;
}

.el-tag {
  margin: 5px;
}

.input-new-tag {
  width: 120px;
  margin: 5px;
}

.button-new-tag {
  margin: 5px;
}
</style>
